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Marine Turtles
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Marine Turtles |
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Species at risk
Find out more about life on the edge.
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What can you do?
Get involved in conservation efforts and tell your friends!
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Saving Planet Earth |
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| Introduction - What are the threats? |
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 | Fishing
Marine turtles are frequently trapped in trawler nets or caught on longline hooks. The turtles can't escape and consequently drown. Bycatch (unwanted catch) is a problem for many marine species, not just turtles. Fishing nets can now be fitted with Turtle Excluder Devices (TEDs) which may help to alleviate the problem.
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| | Migration
Turtles make huge migrations between feeding and breeding sites. Loggerhead turtles, for example, have been tracked on voyages right across the Pacific creating considerable difficulty for conservationists and those conducting research into turtle populations. There is a need for a global approach to protect all migratory species that cross international marine boundaries.
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| | Hunting
In the past, turtle featured regularly on the menus of sailors and explorers as live animals could be kept on board ships as a source of fresh meat. Although no longer part of a sea-faring diet, turtles are still hunted. The shells are used for ornaments or ground up to make traditional medicines and the meat and eggs are eaten in coastal communities and smuggled across the world as delicacies. This illegal trade continues despite being banned by CITES (Convention on International Trade in Endangered Species).
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| | Predators
Although a turtle may lay hundreds of eggs at a time, the hatchlings must make a hazardous journey to reach the sea. They are preyed upon by numerous natural predators including crabs, birds, dogs, foxes, fish and marine mammals. A naturally low survival rate is diminished still further if turtle eggs are taken by humans.
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| | Breeding age
A key factor for turtle survival is the number of adults of breeding age. Some females don't produce young until they are several decades old and they may only breed every other year, or even less frequently. If juveniles don't survive long enough to mate, turtle populations will never recover.
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| | Habitat loss
Adult female turtles return to the beaches where they hatched to lay their eggs. Sadly, they often travel huge distances only to find human development on or near their nesting sites. Turtles are confused by artificial beachfront lighting which causes hatchlings to crawl inland instead of heading for the sea. Once stranded on land, they are usually eaten by predators.
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| | Pollution
The health of the ocean environment is important for all marine species. Pollution from human activity often ends up in the sea. Because turtles may live for up to 100 years, pollutants such as PCBs build up in their bodies and a chemical cocktail is passed on to their eggs. Litter also causes chaos. Plastic bags are a particular problem as turtles mistake them for jellyfish and swallow them. The bags get caught in the digestive tract and cause the turtles to starve.
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